How long to get to parks?

Our flight is landing at 11:30 a.m. on a Saturday in mid-August. We are taking magical express to Pop Century and then planning to ride the bus to Epcot after dropping off luggage. What is a reasonable time to expect to be at Epcot? Trying to plan FPP and dinner reservation. I will make the tier 1 FPP as our last one just in case our flight is delayed.

I would not expect to arrive at Pop until 2hrs after landing, and then allow another 1hr to get to Epcot. So I would not have plans at Epcot before 2:30. You could put in a “throwaway” FPP for starting at 2pm, that way it will expire at 3 if you haven’t used it but will be available to you if you arrive in time.